Update debian.py

issue-: aboutcode-org#3443

src/packagedcode/debian.py

@@ -629,15 +629,22 @@ def build_package_data(debian_data, datasource_id, package_type='deb', distro=No
  keywords.append(keyword)
 
  source_packages = []
- source = debian_data.get('source')
- if source:
+source = debian_data.get('source')
+if source:
+ if distro is None:
+ source_pkg_purl = PackageURL(
+ type=package_type,
+ name=source
+ ).to_string()
+ else:
  source_pkg_purl = PackageURL(
  type=package_type,
  name=source,
  namespace=distro
  ).to_string()
 
- source_packages.append(source_pkg_purl)
+ source_packages.append(source_pkg_purl)
+
 
  return models.PackageData(
  datasource_id=datasource_id,